// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_ARRAYWRAPPER_H
#define EIGEN_ARRAYWRAPPER_H

namespace Eigen {

/** \class ArrayWrapper
 * \ingroup Core_Module
 *
 * \brief Expression of a mathematical vector or matrix as an array object
 *
 * This class is the return type of MatrixBase::array(), and most of the time
 * this is the only way it is use.
 *
 * \sa MatrixBase::array(), class MatrixWrapper
 */

namespace internal {
template<typename ExpressionType>
struct traits<ArrayWrapper<ExpressionType>> : public traits<typename remove_all<typename ExpressionType::Nested>::type>
{
	typedef ArrayXpr XprKind;
	// Let's remove NestByRefBit
	enum
	{
		Flags0 = traits<typename remove_all<typename ExpressionType::Nested>::type>::Flags,
		LvalueBitFlag = is_lvalue<ExpressionType>::value ? LvalueBit : 0,
		Flags = (Flags0 & ~(NestByRefBit | LvalueBit)) | LvalueBitFlag
	};
};
}

template<typename ExpressionType>
class ArrayWrapper : public ArrayBase<ArrayWrapper<ExpressionType>>
{
  public:
	typedef ArrayBase<ArrayWrapper> Base;
	EIGEN_DENSE_PUBLIC_INTERFACE(ArrayWrapper)
	EIGEN_INHERIT_ASSIGNMENT_OPERATORS(ArrayWrapper)
	typedef typename internal::remove_all<ExpressionType>::type NestedExpression;

	typedef typename internal::conditional<internal::is_lvalue<ExpressionType>::value, Scalar, const Scalar>::type
		ScalarWithConstIfNotLvalue;

	typedef typename internal::ref_selector<ExpressionType>::non_const_type NestedExpressionType;

	using Base::coeffRef;

	EIGEN_DEVICE_FUNC
	explicit EIGEN_STRONG_INLINE ArrayWrapper(ExpressionType& matrix)
		: m_expression(matrix)
	{
	}

	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index rows() const EIGEN_NOEXCEPT { return m_expression.rows(); }
	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index cols() const EIGEN_NOEXCEPT { return m_expression.cols(); }
	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index outerStride() const EIGEN_NOEXCEPT
	{
		return m_expression.outerStride();
	}
	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index innerStride() const EIGEN_NOEXCEPT
	{
		return m_expression.innerStride();
	}

	EIGEN_DEVICE_FUNC
	inline ScalarWithConstIfNotLvalue* data() { return m_expression.data(); }
	EIGEN_DEVICE_FUNC
	inline const Scalar* data() const { return m_expression.data(); }

	EIGEN_DEVICE_FUNC
	inline const Scalar& coeffRef(Index rowId, Index colId) const { return m_expression.coeffRef(rowId, colId); }

	EIGEN_DEVICE_FUNC
	inline const Scalar& coeffRef(Index index) const { return m_expression.coeffRef(index); }

	template<typename Dest>
	EIGEN_DEVICE_FUNC inline void evalTo(Dest& dst) const
	{
		dst = m_expression;
	}

	EIGEN_DEVICE_FUNC
	const typename internal::remove_all<NestedExpressionType>::type& nestedExpression() const { return m_expression; }

	/** Forwards the resizing request to the nested expression
	 * \sa DenseBase::resize(Index)  */
	EIGEN_DEVICE_FUNC
	void resize(Index newSize) { m_expression.resize(newSize); }
	/** Forwards the resizing request to the nested expression
	 * \sa DenseBase::resize(Index,Index)*/
	EIGEN_DEVICE_FUNC
	void resize(Index rows, Index cols) { m_expression.resize(rows, cols); }

  protected:
	NestedExpressionType m_expression;
};

/** \class MatrixWrapper
 * \ingroup Core_Module
 *
 * \brief Expression of an array as a mathematical vector or matrix
 *
 * This class is the return type of ArrayBase::matrix(), and most of the time
 * this is the only way it is use.
 *
 * \sa MatrixBase::matrix(), class ArrayWrapper
 */

namespace internal {
template<typename ExpressionType>
struct traits<MatrixWrapper<ExpressionType>> : public traits<typename remove_all<typename ExpressionType::Nested>::type>
{
	typedef MatrixXpr XprKind;
	// Let's remove NestByRefBit
	enum
	{
		Flags0 = traits<typename remove_all<typename ExpressionType::Nested>::type>::Flags,
		LvalueBitFlag = is_lvalue<ExpressionType>::value ? LvalueBit : 0,
		Flags = (Flags0 & ~(NestByRefBit | LvalueBit)) | LvalueBitFlag
	};
};
}

template<typename ExpressionType>
class MatrixWrapper : public MatrixBase<MatrixWrapper<ExpressionType>>
{
  public:
	typedef MatrixBase<MatrixWrapper<ExpressionType>> Base;
	EIGEN_DENSE_PUBLIC_INTERFACE(MatrixWrapper)
	EIGEN_INHERIT_ASSIGNMENT_OPERATORS(MatrixWrapper)
	typedef typename internal::remove_all<ExpressionType>::type NestedExpression;

	typedef typename internal::conditional<internal::is_lvalue<ExpressionType>::value, Scalar, const Scalar>::type
		ScalarWithConstIfNotLvalue;

	typedef typename internal::ref_selector<ExpressionType>::non_const_type NestedExpressionType;

	using Base::coeffRef;

	EIGEN_DEVICE_FUNC
	explicit inline MatrixWrapper(ExpressionType& matrix)
		: m_expression(matrix)
	{
	}

	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index rows() const EIGEN_NOEXCEPT { return m_expression.rows(); }
	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index cols() const EIGEN_NOEXCEPT { return m_expression.cols(); }
	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index outerStride() const EIGEN_NOEXCEPT
	{
		return m_expression.outerStride();
	}
	EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index innerStride() const EIGEN_NOEXCEPT
	{
		return m_expression.innerStride();
	}

	EIGEN_DEVICE_FUNC
	inline ScalarWithConstIfNotLvalue* data() { return m_expression.data(); }
	EIGEN_DEVICE_FUNC
	inline const Scalar* data() const { return m_expression.data(); }

	EIGEN_DEVICE_FUNC
	inline const Scalar& coeffRef(Index rowId, Index colId) const
	{
		return m_expression.derived().coeffRef(rowId, colId);
	}

	EIGEN_DEVICE_FUNC
	inline const Scalar& coeffRef(Index index) const { return m_expression.coeffRef(index); }

	EIGEN_DEVICE_FUNC
	const typename internal::remove_all<NestedExpressionType>::type& nestedExpression() const { return m_expression; }

	/** Forwards the resizing request to the nested expression
	 * \sa DenseBase::resize(Index)  */
	EIGEN_DEVICE_FUNC
	void resize(Index newSize) { m_expression.resize(newSize); }
	/** Forwards the resizing request to the nested expression
	 * \sa DenseBase::resize(Index,Index)*/
	EIGEN_DEVICE_FUNC
	void resize(Index rows, Index cols) { m_expression.resize(rows, cols); }

  protected:
	NestedExpressionType m_expression;
};

} // end namespace Eigen

#endif // EIGEN_ARRAYWRAPPER_H
